Situating the salience and parietal memory networks in the context of multiple parallel distributed networks using...

Area of Science:

• Neuroscience
• Cognitive Neuroscience
• Neuroimaging

Background:

• Higher cognitive functions rely on distributed brain networks across frontal and posterior association areas.
• The parietal memory network (PMN) and salience network (SAL) were previously considered distinct, localized to posterior and anterior regions, respectively.
• Traditional neuroimaging resolutions may obscure the full extent of these networks.

Purpose of the Study:

• To investigate the precise anatomical organization of the PMN and SAL using high-resolution neuroimaging.
• To determine if the PMN and SAL represent a single, unified network.
• To explore the functional relevance of this unified network in cognitive tasks.

Main Methods:

• Utilized high-resolution neuroimaging (3T and 7T) to obtain detailed brain network estimates.
• Performed individualized network mapping to delineate the boundaries of the PMN and SAL.
• Conducted task-based analyses focusing on recognition to assess network activity.

Main Results:

• Individualized PMN estimates extended beyond posterior regions to include frontal and insula areas typically associated with the SAL.
• This unified network was termed the "SAL/PMN" network.
• Both anterior and posterior components of the SAL/PMN network exhibited recognition-related activity.
• High-resolution (7T) data more clearly revealed the unified SAL/PMN structure compared to lower-resolution (3T) data.

Conclusions:

• The PMN and SAL constitute a single, unified brain network, the SAL/PMN.
• This unified network aligns with the expected parallel distributed organization of association cortex.
• High-resolution neuroimaging is critical for accurately mapping fine-grained brain network structures.